Slide fasteners include first and second stringers. Each stringer includes a tape and a plurality of standard elements disposed along an inner edge of the tape. The tapes lie within a fastening plane, and the inner edges face each other within the fastening plane. A slider is slidably coupled to at least one of the stringers. The slider couples the plurality of elements of the stringers when the slider is urged in a first sliding direction within the fastening plane and decouples the element when the slider is urged in a second sliding direction within the fastening plane. The first sliding direction is opposite the second sliding direction. The standard elements have the same contour and are engagable with each other when the slider is urged past opposing elements.
With this arrangement, suppliers of a replacement product that includes one or more stringers of the slide fastener may be able to compete for sales with an original supplier of the product that includes the slide fastener. However, the original supplier and/or the purchaser may wish to prevent the other suppliers from providing the replacement product. Accordingly, there is a need in the art to provide a modified slide fastener that prevents engagement compatibility with standard elements.